Computing machine



June l, 1943.

w. A. ANDERSON 2,320,399

NNNNNN OR June 1, 1943. w. A. ANDERSON COMPUTING MACHINE Filed June 26, 1940 5 Sheets-Sheet 2 INVENTOR WALTER A. ANDERSO/Y ATTORNEY June l, 1943. w. A. ANDERSON 2,320,399

COMPUTING MACHINE Filed June 26, 1940 3 Sheets-Sheet 3 WALTER A. ANDERJON ATTORNEY Patentecl June 1, 1943 COMPUTING MACHIN E Walter A. Anderson, Bridgeport, Conn. assignor to Underwood Elliott Fisher Company, New York, N. Y. a corporation of Delaware Application June 26, 1940, Serial N0. 342,544

1 Claim.

This invention relates tu adding machines, and more particularly to machines of this dass that are used in merchandising transactions and the 1ike.

G-enerally these machines record individual purchases, together with the totals thereof, upon a slip that is handed to the customer as a record of the transaction. It is desirable on such machines to have a registered count of ehe number of such completed sa1es or transactions made within a given periocl. These machines are generally equipped with a motor bar and total key, both of which are adapted to cycle the machine, the motor bar being used to cyc1e the machine following the indexing of items upon the amount keys t0 cause the items so be printed 011 the slip and accumulated in a totalizer, and the total key being used to cycle the machine to print the total and clear the totalizer following the printing and accumulation of a group 0f items. Thema is a possibility that following the indexing of an item, the operator might strike the total key instead of the motor bar. This would causethe item to be printed without being accumulated in the totalizer, and result in an erroneous total of the items listed upon thes1ip.

It is an object of the presentinvention, therefore, to provide a means that positively insures accumulation in the totalizer of all items indexed on the amount keys whether the machine is operated by the total key or the customary motor bar.

Another object of the inventiou is to provide a machine of this character with a simple and efiective means for counting the number of totals, and that is operable to count 1 on1y upon the totaling cf a transaction.

With these and incidental objects in view, the invention consists in certain novel features of construction and combinations of parts, the essential elements of which are Set forth in appended claims, and. a preferred embodiment of which is hereinafter -described with reference to the drawings which accompany and formpart of the specification.

In the drawings:

Figure 1 is a perspective view of an adding machine on which the invention is adapted to be used,

Figure 2 is a right side elevation of the machine embodying the features of my invention, the parts being shown in normal Position,

Figure 3 is a perspective view generally similar ;o Figure 2 but with the mechanism occupying an intermediate position, in the course of an operation,

Figure 4 is a right side elevation 01? the total counter, together With certain of the parts used for the operation thereof,

Figure 5 is a fragmental right side elevation 0f the totalizer, together with certain of its comtro1 mechanism,

Figure 6 is a detai1 right side elevation showing the connection between ehe total key anal the motor bar, and

Figure 7 is a detail perspective of a blank cyc1e control detent.

The invention is shown as app1ied to a machine of the character disclosed in U. S. Patents GENERAL DESCRIPTION This is an improvement on machines disclosed in the above-enumerated patents. The machine is adapted to be mounted on a cash .drawer, and is equipped With a keyboard including amount keys for indexingthe amounts of iterns to be added a motor bar for cycling the machine. so add theamounts in the totalizer, and a total key for cycling the machi'ne to print the totals cf the accumulated amounts. It is provided with the usual paper carriage that supports a ta1ly roll arranged to be 1ine space advanced incident to each operation of the machine around a roller platen.mounted in the carriage. Type bars are provided for printing the item amounts and the totals upon the tal1y. A pla'te having a serrated edge is mounted on the carriage to facilitate the tearing of the completed slip, of recorded transactions. A total counter is provided on. the left of. the keyboard to count 1 fon eachtotal taken. It is so constructed that it; willcount on1y l? even though the totalkey shou1d beheld down' to .permit cy.cling of the machine after the.total is printed.

In Ehe ordinary course of operations, an itern amount is indexed on the amount keysand the motor bar depressed to cyc1e ehe machine.. During thisoperation, the type bars riseto .print the amount of the:item and then return tonormal position. During theascenc of thetype bars, the totalizen is=disengaged from actuationracks carried by thetype barsbutjustprior to 'the descent of the bars, thetotalizer is re-engaged with the racks so that the amount printeclis aceumulated thereon. 1

When all of the items that-re to be added in a given transaction have been accumulated,

the operator depresses the motor bar to initiate what is known as a blank cycle to condition the machine for taking a total. The total key is then depressed, and, through its connection with the motor bar, initiates a total cycle. During this cycle of the machine the totalizer remains engaged with the actuating racks during the ascent of the type bars, and is disengaged from the racks just prior so the descent of the bars, leaving the totalizer cleared in readiness for the next group -of accumulating operations.

Although normal operations of the machine are performed as outlined above, i. e. operation of the motor bar following the indexing of an item will cause the item to be added on the totalizer, and operation of the total key following a completed item entering operation will cause a total to ibe taken from the totalizer,'

mechanism is provided whereby operation of the total key instead of the motor bar following the indexing of an item will also cause such indexed 1 item to be accumulated on the totalizer.

DETAILED DESCRIP'I'ION Index topics l. The machine sections and operating mechanism. V

2. Indexing, differential and printing mechanism;

3. Totalizer engaging and disengaging mechanism.

4. Adding an item.

5. Means of enforcing a blank cycle before taking a total.

6. Taking a total.

7. Means for preventing non-addition of items.

8. Counting totals.

1. 'Im: MACHINE SECTIONS AND OPERATING MECHANISM Referring to Figure 1, the reference numeral I indicates the machine generally, mounted upon a cash drawer 2. The machine is equipped with the usual carriage 3 having a platen 4 arranged. to 1ine space advance the paper during each machine cycle, from a tally roll supply that is supported on the Carriage. A platze 6, serrated along its upper edge, is mounted on the carriage to facilitate tearing of completed sa1es slips. The machine also has the customary type bars 1, keyboard 8 including amount keys 9, motor bar I2 and total key I3. A totalizer I4 (Figure 5) comprisedof a plurality of twenty tooth wheels and operable by actuating racks I5 suspended from type bars 1, is arranged to add items indexed upon amount keys 9. The totalizer is comdi-tioned by total key I3 for taking totals of the added amounts and a counter I5 (Figure 1), mounted to the 1eft of the amount keys and viewed through an aperture in ehe machine housing, is adapted to count the Isota1s and thereby register the number of completed transactions. 1

The machine is operated by an eleotric motor I1. The motor is started rby the closing of a suitab1e sWitch mechanism and is coupled with an actuating shaft I8 (Figures 2 and.3). by a suitable clutch mechanism upon depression of either motor bar I2 or total key I3. As shown in Figure 6, motor bar I2 carries a slide pivoted to an arm 2I of a rod 22 oxtendi ng across the front cf the-inachine. An upwardly directed arm 23 of rod 22 is connected to a link 24 extending to the rear of the machine, where it concrols obe c losing and opening of the switch and engagrement and disengament of the c1utch, as above described. The connections of link 24 with the switch and clutch mechanism are disolosed in Patent N0. 1925735. An arm 25 pivoted on slide 20 is yieldingly he1d in contact With a pin 26 fixed on total key I3, so that depression of this key also operates slide 20 to initiate a machine cycle.

Operation of the motor causes drive shaft I8 to oscillate counter-clockwise, then clockwise (Figures 2 and 3), once during each maohine cycle.

2. INDEXING, DIFFERENTIAL AND PRINTING MECHANISMS The above mechanisms are identical W'lth those disclosed in the hereinbefore enumerated patents so that the explanation thereof Will be on1y general.

Itern amounts to be entered in the machine are indexed 'on the amount keys 9 which sei: horizontally disposed Shops (not. shown) into the path of a series of rods such as 21 (Figures 3 and 5). Rods 21 are connected ab their lower ends to arms such as 28 pivoted to type bars 1 mounted for vertical movernent in I;he maohine. Rods 21 are guided in a frame 3I that is slidable along a rod 32 from 1eft to right in the machine. A series of type carried by each type bar cooperate with platen 4 to print amounts and totals, a series of harnmers similar to those disclosed in the above-mentioned patent's being provided 150 efiect printing. The type barS I and actuating racks I5 suspended therefrom are suitably arranged to be raised and lowered during each. cycle of I;he machine by mechanism Such as that fu1ly disclosed in PatentNo. 1,965611.

As the amount keys are der ressed a suifiable escapen1ent causes frame 3I move fr0m left; to righl; (Figure3) one step for each amount key depressed, placing rods 21, one at a time, befieath the'stops that have been Set by the amount In the indexing of an item, as the first amount key is depressod, a suitable' conr'1eotion moves a lever 33 (Figure '3) clockwise about its pivot 34 to move a plate 35 toward the real (as viewed in Figure 3) a slight extent about its pivoi: 3 6. Movement of plate 35 rearwardly, moves the forward end 31 of a platze 38 rearwardly in the machine. The rear end of plate 38 is pivoted ab 4I to a frame 42 composed of two similar members, one on each side of the machine, pivoted on a rod 43 and connected by a rod 44 for uniform movemen1p. A pair of springs 45 connected to theupper ends of the franr 1e members tend to move plate 38 forward, bu t are prevented by a spring detent 45 (Figure 7), fi'om doing so after it is moved rearwardly by p1ate 35.

Rearward movement of plate 38 places the end 31 (Figure 3) above rods 21, so that during the printing of an item, only the rods that are mov'ed the right of the plate are permitpted to rise dur'ing the machine cycle. In this manner, on1y the type bars nec'essary to print the digits of an indexed number are allowed to risefrom their zero positions. v

3.TOTALIZER ENGAGING AND DISENGAGING MECHANISM and right, Figure 5). T0 sh1ft thetotalizer 1n this manner, an arm 48 (Figures 2 and 3) connected wit-h actuating shafc I8 carries a pawl 5I pivoted at 52 on the arm. This pawl engages studs 53 and 54 on the initial and return strokes of the actuating shaft t;o oscillate a platze 55 carrying studs 53 and 54 first counterclockwise then clockwise during each machine cycle.

Oscillation of plate 55 moves a stud 58 (Figure 5) embraced by a cam slot 51 in plate 55, and a link 58 to the left and then to the right, stud 58 being carried by an arm 6I pivoted at 62 and connecting the forward end of link 58 with arm EI. Link 58 at its rear end has a notch engaging a stud 63 on one of two sirnilar levers 64 secured to a shaft 65 journaled in the machine frarne. Two identical links 68 conneot levers 54 With shaft 4'I. When the machine is cycled to add an item, movement of link 58 110 the left at the beginning of an operation, moves the totalizer from the position shown in Figure 5, where it is engaged with racks I5, a slight distance to the left to a position where it is disengaed from the racks. Movement of link 58 to the right at the beginning of the second half of the cycle returns the totalizer to the position shown in Figure 5.

The same parts are used. for engaging and disengaging the totalizer with the actuating racks for taking totals, with the exception, however, that; a hell crank 59, loosely pivoted on drive Shaft I8, cooperates with a link 58 connected between one arm of the hell crank and plate 55 to disengage the totalizer ab the beginning of the second half of the cycle, and a fiange 89 secured to arm 48 cooperates with the horizontal arm of hell crank 58 to engage the totalizer at the end of the operation, as will be explained in detail later.

4. ADDING AN ITEM'.

T add an item. the item is indexed on the amount keys 9 and the motor bar depressed. Oscillation of drive shaft I8 (Figure 2), through pawl I and stud 53, disengages the totalizer from the actuating racks. During the rernainder of the first half of the cycle, type bars I (Figure 5) rise difierentially until their rods 21 abut the stops (not shown) that are difierentially Set incident to the indexing of an item on the amount keys 9, actuating' racks I5 rising with the type bars.

At the beginning of the last half of the cycle, pawl 5I engages stud 54, returning plate 55 link 58 lever 84, link 88 and the totalizer to their positions shown in Figure 5, where lt is engaged with racks I5. During.the remainder of the last half of Ihe cycle, the type bars and actuating racks are lowered in the usual manner, entering on the totalizer the amount indexeci on the keyboard.

5. MEANS OF Enroacmc. A BLANK CYCLE BEFORE Turms A TOTAL Mechanism similar to that shown in Patent N0. 1583102 is provided on this machine 130 enforce a blank cycle before a total can be taken, so that any of the parts of the customary transfer mechanisrn employed on machines of this type that were tripped during the last; accurnulating operation, will be restored.

'Io do this, it is on1y necessary to hold all the rods 21 (Figure 3) against rising during the cycle. This is accomplished by leaving the end 31 of plate 38 ai; the end of an accumulating operation in its rear position where it overlies rods 2'I, lt being remembered that; depression of .the first amount keys in indexing an amount moves plates 25 and 38 into their rear positions. With plate 38 in its rear position, if n0 amount keys are depressed, all the rods 21 lie under the p1ate, so that during operation of ehe machine, the type bars are held from rising. During such a blank operation, as explained in Patent N0. 1,583,102 plate 38 i moved forwardly to i'bs position shown in Figure 3, so that a total can be taken in the following operation.

6. TAKING A TOTAL In taking a total, the total key I3 is depressed. Depression of this key, through its connection with motor bar I2 (Figure 6) as before described, initiates a machine cycle,

Depression of total key I3 withdraws a stud 6'I, connected thereto, fr0m its position directly beneath a lever 68 (Figure 2), and stretches a spring II connected between lever 68 and. the machine frarne.

Movement of plate 38 forwarclly to its p0sition shown in Figure 3, during the preceding blank cycle, moved frame 42 forward with it. Forward movement of the frame frorn the position shown in Figure 2 to that shown in Figure 3, through a pin I3 fixed in the frame, moved a lever 14 counter-clockwise about its pivot 15 by reason of the end of pin 13 lying Within a slot in lever 14. 'Ihis movernenb of lever 14 causes a flange 15 thereon (Figure 2) to strike pawl 5I, and move it sufficiently to prevent it from cooperating with stud 53 at the beginning 0f the total taking operation. Therefore, the totalizer remalns engaged With the aCtuating racks during the first portion of the operation, allowing the actuating racks and. type bars to be moved difierentially under control of the totalizer wheels.

T0 disengage the totalizer alter the wheels are returned to zero by the differential upward movement of the racks, the following mechanism is proVided to move plate 55 counter-ciockwise by counter-clockwise movement of hell crank 59 as mentioned above, at the beginning of the second half of the total taking cycle.

A cam lever 'I'I pivoted ab 8I has a slot I8 that embraces a rod 82 and is provided on its 1ower edge with a notch 83 (Figure 3). Rad 82 is fixed in an arm 84 pivoted ab 85, that is arranged, through suitable connections with accuating shaft I8, 130 be rocked first clockwise, and then counter-clockwise about pivot 85 during each cycle 0f the machine. Another cam lever 88 also is pivoted at 8I and is tensioned counter-clockwise by a spring 81. Lever 86 has a carn edge 88 that bears against tl1e lower side cf rod 82, under the tension of spring 8'I, and has a short cam slot 9I in its lower edge, and a hook 92 at its upper end. A lever 93 (Figure 2) is pivoted on a rod 94 and is tensioned counter-clockwise by a spring 85, the counter-clockwise rnovement of the lever being controlled by rod 82 upon which the lower edge of the lever rests. Lever 83 carries a stud 96 which normally lies out of the pabh of hook 92.

During accumulating operations and during the blank cycle preceding a total taking cycle, in other words, during the operations in which frame 42 is in its rear position, as shown in Figure 2, a stud 91 on lever 14 lies in its rear position shown in Figure 2. During these operations, the forward movement of rod 82, during the first half of the machine cycle, allows lever 83 to move a sufificient distance counter-clockwise to bring stud 86 into the path of hook 92. Then upon rod 82 reaching its forward extremity,

where lt moves lever 77 cou'nter-clo0kwise, because of the configuration of the left end of cam slot I8, notch 83 is placed directly above a stud 98 secured 120 the rear end of lever 68 and resting on the lower eclge of lever 86. I-Iowever, slnce stud 96 is in the path of hook 92, lever 86 is held agalnst any substantial counter-clockwise movement from its position shown in Figure 2. Stud 98, therefore, does not rise inI;o notch83, laut remains helcl in 1'ts lowerecl position by lever 86. Lever 68 is thereby held agalnt operation dnring these cycles even though total key I3 ls depressed, to tension spring 1I and thereby tension lever 55 counter-clockwise.

During a total taking operation, however, frame 42 and lever 14 are in their forward positions (Figure 3) where stucl 91 lies directly under the forward end of lever 93. Therefore, assoon as rod 82 begins its forward movement, lever 86 begins moving counter-clockwise, and since tl1e total key I3 1's depressecl, spring II is stretched, tensioning stud 98 upwarclly towarcl the lower edgeof lever 71. As rod 82 cornpletes its forward movement, lever 11 moves counter-clockwi'se, as mentioned above, placing notch 83 above stud 98. Since lever 85 has moved counter-clockwise, stud 98 1s permitted to rise into notch 83, whereupon further counter-clockwise movement of lever 86 moves slot 9I therein into engagement with stud 98, locking the stud in notch 83, as shown in Figure 3. This rising of stucl 98 is accompanied by a sufilcient risingof the rear portion 0f lever 68 to place a shoulder IIII I;hereon immediately behind a stud I 02 011 hell crank 59.

Durlng the first part of the return movement of shaft I8, rod 82 moves lever l"! clockwise so its posltlon shown in Figure 3 moving stud. 98 ancl lever 88 forwardly. This causes shoulder IIII 'to move stud IIJ2 and rock hell crank 59 counterclockwise which in turn, through llnk mnnetion EI), moves plate 55 counter-clockwise as desired, to disengage the totalizer from the actuating racks before they are lowerecl 130 their normal positlons, shown in Figure 5. The totalizer now stands at zero. During the remaincler of the retum movement (f shaft I8, rod 82 is moved to the rear, moving lever 86 clockwiseto its position shown in Figure 2. Thls cams stucl 98 downwardly out of notch 83, whereupori a spring I83, connected to lever 68, pulls the lever and stud 98 130 the rear to their positions shown in Flgure 2. During the last portion of the return movemenl; of shaft I8, flange 69 S131lk85 the horizontal arm 01 hell crank 59, and moves the hell crank clockwise, movlng plate clockwise to its position shown in Figures 2 and 5, leaving the totalizer engaged Wlth I:he actuating racks at the end of the operation.

. The following parts are provided to hold pawl 5I away from stud 54 durlng total taking operations so that plate 55 may be roeked counterclockwise by hell crank 59 and link as just describecl. -A slicle III4 (Flgures 21 and 3) 1's mounted. 011 studs I for movement forwardly' and rearwarclly of the machine (left and right in Flgures 2 and .3). The slicle is normally urged toward the right by a spring III6 laut 1's prevented from moving to its extreme rearwaid (right) positio n by a flange I0l that engages a shoulder 183 formecl on the sllole, Flange III! is secred on a lever III pivoted ab II21the' forward end of which underlies an extension Il3 on the stem of total key I3. The right end of the slide has a cam surface I I 4. Upon depression of total key I8, extension,

II 3 rocks lever III, withdrawing flange IO'I from the path cf movement of shoulder III8 and allowing the slide IM to move its stroke of its oscillation and thrusts the slide toward the left, whereupon fiange III! is again raised'into the path of shoulder III8 by.suitable spring tension upon lever III.

7. MEANS FOR PREVENTINGNONAI5DITION OF ITEMSI In ma chlnes of ehe tjzpe illustratrd in the diavlfings, but n ot providecl With the present improvement, lf the operato1fl should strike the total key instead of the motor bar following the indexing cf an i te m the machinewouldexecu te a cycle becanse of the above described connectlons between I;he total key and the motor bar. During this cycle, totalizer I4 would be disengagepl from the rackS during the first portion of the cycle, and

the amount indexed would be prlnted blit non added on thetotalizer, because the rearward movement of slide 104 inciclent 1:0 operation of tne total key placed cam surface II4 in effeiztlvl positioii preventing re -engagement of the total izer with racks I5 prior to the seconcl or adding portion of the cycle.-

Th e following parts are proVided to insi1re the.

addition of such ltems eVen thongh thetotal key is so misoperated. A lock lever I 2I (Figure 2).

pivoteol on a. stucl I22, has a flange I23 lying above tne rlght end of slicle II l4, and ls connected by a pln-and slot connection I24 at its left end to an arm I25 fixedon a rod I2Ii journaled in the machi'ne frame (see also Fig. 3). A dependlng fingerl2'l fixeol on rod I26 lies in front of a rollen I28 carried by a sliole I 3I, a spring I32 tension Ing finger I'21 against; roller I28. Slide I'3I co'rresponds to the slide bar 72 in Patent N0. l198487 anal is operable as disclosed in that patent to advance step by step toward the right, as viewecl in Flgures 2 and 3, and toward the left as vlewed in Figure 4, incident to digit-by-digit indexing of a number on amount keys 9. 'Tl1e Slicle is also Operable, as explained in that patent to restorefrom any such aclvanced position 1ts normal position shown in Figures 2 ancl 3, upon the completion 'of amachine operation.

As I:he first digit of an item is indexed.in the Keyboard, sllde I3I .advances one step of movement toward the right, as viewed in Figures 2 and 3, and finger I 21, following the roller I28 under tension of spring I32, rocks shaft 'I26, which in turn, by pin-and-slot connection I24, rocks lever I 21 clockwise, l0wering flange I 23in- I;o tl1e pathof movement of slide IM. In such position, fiange 123 locks slide I4 in its forward o1 left position, preventing cam surface II4 from being rnoved intoelfective position with respect to pawl 5I. Hence, even though total key I3 is struck following the indexing of an item on the Keyboard, I;he item will be addd in the tofia1izer. Upon completion of the cycle, as sl1de I3I ls restored to normal position, roller I28 strikes finger l21, rocking flange I23 upwardly out of the path0f move'ment of slide I 04 shown in Figure. 2. Leck lever ineffective position during to the posltion I2I remair'1s in totaling operatl0ns;

since during the blank cycle preceding such operation no item is indexed upon the Keyboard, and hence slide I3l remains in normal position i. e., holding lever I2I inefiective against tne tension exerted by spring 132.

8. COUNTING TOTALS A counter IG, suitably mounted in the machine frame to the left cf keyboard 8, is viewed. through an aperture in the machine housing (Figure 1) and is provided 130 count the number of totals taken. This counter is of the well-known Veeder type, comprised of a series of pinions arranged for step-by-step counting incident to oscillation of an actuating shaft i33 (Figure 4). An arm l34 (Figures 3 and 4) flxed on the shaft; is connected by a 1ink I35 t an arm 136 loosely mounted on a rod I3'l journaled in the machine frame. An arm I42 fixed on rod 131 adjacent arm 136 is yieldingly connected to arm l36 by a spring M3. Arm 142 carries a stud IM engageable by a latch 145 loosely mounted on shaft 125 and yieldingly connected by a spring 146 to an arm M! fixed on shaft 126 adjacent the 1atch.

Upon indexing an item on amount keys 9, as s1ide I3l moves away from finger I2'l as shown in Figure 4, latch M is raised under tension cf spring 132 to release stud l44. Thereupon, arm I34 swings counter-clockwise, as viewed in Figure 3, under the tension cf a, restoring spring (not shown) within the counter, 120 the position shown in Figure 4. Arm l34 remains in this position until the taking of a total. A depending finger I38 fixed on rod I3! lies in front of a pin |4| carried by lever 68. When 1ever 68 moves forward during a total taking operation as described. in a preceding section, pin Ml rocks finger I38 clockwise, as viewed in Figure 3, rocking arm I34 clockwise to effect a count of l in the counter. Incident to this clockwise movement of arm l34, stud I44 is again engaged by Patch [45, the latch now being in its lower effective position since no item has been indexed on the keyboard. Arm 134 remains held by the latch against the restoring action of the munter-spring until the next item is indexed on the Keyboard, and so on.

By this arrangemenb, a. count of 1 Will on1y be effected upon the taking of a total, irrespective of the number of times total key 13 may be depressed following tne taking of that total.

Tne yielding connection between arms l35 and M2 prevents overthrow cf arm l34 incident to forward thrust of lever 68, and the yie1ding counection between latch and. arm 141 permits stud IM to enter the confines of the latch when the latter is in its 10Wer or effective position.

While the form of mechanism herein shown and described is admirably adapted to fu1fill the objects primarily sbated, it is to be understood that it is not intended to confine the invention to the one form of embodiment herein disclosed, for it is susceptible of embodiment in various forms all coming within the scope of the claim which follows.

What is claimed is:

In a machine of the dass described, amount keys, a total key, a totalizer, actuating racks, means to engage anal disengage the totalizer with the actuating racks for item entering and total taking, a connection from the total key to the engaging means to contro1 the operation of the engaging means during total taking operations, and a connection between the amount keys and the first mentioned connection to render the first mentioned connection ineffective up0n operation of an amount key.

WALTER A. ANDERSON. 

